1. Field of the Invention
The present invention relates generally to an improved data processing system, and in particular, to a computer implemented method for data communications in a data processing environment. Still more particularly, the present invention relates to a computer implemented method for selective link aggregation in a virtualized data processing environment.
2. Description of the Related Art
Data processing systems can be divided into logical partitions (LPARs). A logical partition is also known as a logical partitioned data processing system, or simply as a “partition”. Each partition operates as a separate data processing system independent of the other partitions. Generally, a partition management firmware connects the various partitions and provides the network connectivity among them. Hypervisor is an example of such partition management firmware.
A partition or another commonly used data processing system may access one or more data storage devices for reading, writing, storing, and managing data. A partition may also access one or more data communication network (network) for sending and receiving data, such as from a data storage device. A network may be a local area network (LAN) or a wide area network (WAN).
In some partitioned data processing systems, virtual input/output (I/O) servers provide the partitions access to one or more network or data storage device. A data storage device may include one or more physical data storage units, such as hard disks, as in the case of a storage array, or a storage area network (SAN).
A partition, with or without the use of a virtual I/O server may access a network over more than one data communication paths. A communication path is also called a link. A link typically facilitates data communication between an I/O adapter and a data port, such as a port on a switch. A switch is any device that facilitates data communication between two or more data processing systems or components thereof. A common variety of switches enables multiple data processing systems and networking capable data processing system components to communicate with each other, with a data network, or both.
A partition utilizing multiple links to communicate with a network may use multiple I/O adapters or multiple ports on an I/O adapter to communicate with multiple corresponding ports on a switch. Each I/O adapter port communicates with a port on the switch. An I/O adapter port is a point of ingress and egress of data to and from the I/O adapter. Similarly, a port on a switch is a point of ingress and egress of data to and from the switch.
Multiple links can be logically grouped together so that they appear to a partition and a switch as a communication channel of multiple links between the partition and the switch. The communication channel hides the individual I/O adapters or I/O adapter ports from the applications using those adapters for data communication such that data communication from such an application can be serviced by any of the I/O adapter ports participating in the communication channel. A group of multiple links operating as a communication channel in this manner is called a link aggregation channel.
Link aggregation channel configurations are commonly employed in data processing environments for increasing the data throughput rates between a data processing system and a switch. Link aggregation channels also improve the reliability of the data communications between a data processing system and a switch by providing redundant data communication paths between them.